Field of the Invention
The present invention relates to a living body stimulator such as an ECP (external counter pulsation) device for curing and treating a living body by supplying a fluid pressurized by a pump to a bag worn by the living body.
Background Art
EPC devices as living body stimulators have been mainly used to treat heart diseases. However, in recent years, such EPC devices have also been used as auxiliary devices for performing beauty and sports treatments. Each of JP-A-2004-261592, JP-A-2008-200224 and Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2004-523260 discloses a detailed structure of such EPC device.
During systole, the heart of a human body as a living body pumps blood to each section of the human body. In contrast, in diastole, the blood returns to the heart largely owing to the muscle movements of the human body. Particularly, the muscles of the lower limbs that are distant from the heart are often referred to as the second heart. That is, these muscles play a significant role. An EPC device is therefore a device used to return the blood to the heart by pressurizing and thus stimulating the lower limbs and the lumbar area during diastole as a passive state of the heart. Specifically, this is carried out by supplying an air pressurized by an air pump to an airbag(s) wound around each lower limb or the lumbar area.
Each of the EPC devices disclosed in JP-A-2004-261592, JP-A-2008-200224 and Japanese Unexamined Patent Application Publication (Translation of PCT Application) No. 2004-523260 is configured in a manner such that the pressurized air is supplied from a single and shared air pump to multiple airbags through an air tank. FIG. 10 is a diagram schematically showing this configuration.
In FIG. 10, a conventional ECP device 100 includes a single air pump 1 for generating a pressurized air; an air tank 2 for retaining the pressurized air from the air pump 1; and at least one pressurization airbag 3 that is to be attached to a treatment area of a human body. In general, a plurality of such airbags 3 are connected to a single air supply circuit 5 having the single air pump 1 and the single air tank 2. As shown in FIG. 10, the conventional ECP device 100 employs three airbags 3-1 to 3-3 that are capable of being individually attached to the upper part of the thigh, the lower part of the thigh and the calf part of a human body.
Here, the outlet of the air pump 1 and the inlet of the air tank 2 are communicated with each other through a first flow passage 11 as a part of the air supply circuit 5. Further, the air tank 2 is provided with the same number of outlets as the airbags 3-1 to 3-3. Particularly, these outlets of the air tank 2 are individually communicated with the airbags 3-1 to 3-3 through second flow passages 12-1 to 12-3. Open-air passages 13-1 to 13-3 whose front ends are open to the atmosphere, are individually communicated with the midway sections of the second flow passages 12-1 to 12-3. In addition, injection magnetic valves 15-1 to 15-3 are individually connected to the sections of the second flow passages 12-1 to 12-3 that extend from the outlets of the air tank 2 to the base ends of the open-air passages 13-1 to 13-3. Other than the injection magnetic valves 15-1 to 15-3, discharge magnetic valves 16-1 to 16-3 are individually connected to the open-air passages 13-1 to 13-3.
Attached to the air tank 2 are a pressure sensor 21 for sensing the pressure inside the air tank 2; and a leakage valve 22 for discharging to the atmosphere a small amount of the pressurized air from the air tank 2. Both the pressure sensor 21 and the leakage valve 22 serve to control the speed of a motor as a driving source of the air pump 1.